Reduced intergroup differentiation as a result of self-categorization in overlapping categories. A quasi-experiment

A quasi-experiment was conducted to examine the effects of self-categorization in overlapping categories on intergroup differentiation. ‘Old aged women’ was used as the first, ‘sports’ as the additional category. It could be shown that intergroup differentiation was significantly reduced under crossed categorization conditions. Implications for social compensation strategies are discussed.     

Subject knowledge of the Experimenter''s interest in handedness and familial sinistrality variables and laterality test outcomes

We investigated the possible influence of common "demand characteristics" on the results on behavioral language laterality tasks. The demand characteristics were (1) whether Ss were or were not recruited for study according to their handedness, and (2) whether a detailed familial sinistrality inquiry was conducted before or after the tasks. Tasks were the Dichotic Consonant Vowel Task (DCVT) and the Bilateral Object Naming Latency Task (BONLT). Results showed no effect of demand characteristics on the BONLT. On the DCVT, however, prior inquiry regarding familial sinistrality was associated with significantly reduced right ear advantages (REAs). Interactions showed that the greatest reduction in REAs occurred in Ss with left-handedness in their families, who were asked about familial sinistrality prior to the tasks, who took the DCVT after the BONLT, and who were also recruited by handedness. Results, though generally reassuring regarding the robustness of the tasks against these sources of bias, raise some cautions for the DCVT.     

Interactions between area and numerosity

Summary The concept of filled area, i.e. the impressionistic ensemble of parts of a stimulus field occupied by dots, is used to account for various kinds of numerosity illusions due to perceptual interaction between a number of dots and their spatial arrangement. A measure of filled area is derived from a model for the perceptual clustering of dots on the basis of relative proximity. It is shown that the quantified concept of filled area successfully predicts illusion data from earlier studies. Subsequently, a two-alternatives forced-choice numerosity experiment is reported, the data of which gave further evidence of the predictive power of the filled-area hypothesis. Our approach is discussed with respect to spatial features of dot stimuli that might be in rivalry with the filled-area factor in numerosity-estimation tasks.     

Does spreading activation summate?

Summary Network models of semantic memory assume implicitly or explicitly that the degree of activation of a node is a monotonic function of the total amount of excitation reaching that node from all sources. For example, the activation level of the node representing apple should be greater if it is receiving excitation due to the activation of the nodes for fruit and pear than if only one of these neighboring nodes is activated. This notion was tested by presenting semantic primes 80 ms or 320 ms before a letter string (e.g., apple or ipple) requiring a lexical decision. The prime stimuli consisted of a pair of simultaneous items that were identical in the single prime condition (e.g., fruit/fruit or pear/pear) or different in the double prime condition (e.g., fruit/pear or pear/fruit), and were either related (target = apple) or unrelated (target = copper) to the target, or neutral. As predicted by the summation of semantic activation assumption of network models there was a larger priming effect (in the 320 ms SOA condition) following the simultaneous activation of two related nodes than following the activation of only one node.This research was supported by grants to the first author from the Natural Sciences and Engineering Research Council of Canada.     

Evaluation of a mutual help network for the elderly residents of planned housing

We set up a mutual help network among the elderly residents of a government-subsidized apartment building and evaluated its impact on their social ties, social support satisfaction, and depression. A quasi-experimental design was used, with the residents of a similar building located in the same neighborhood serving as the control group. A total of 230 individual services were exchanged, and 28 group activities were organized during the study period. There was almost no difference between experimental and control groups with respect to the change over the study period in the number of social ties with other residents of the building. Support satisfaction decreased in both groups, but the decrease was larger in the experimental group. The control group had a slight decrease in the frequency of their depressive symptoms, whereas the experimental group had a moderate increase. More research is needed on the ability of social support interventions to produce beneficial effects on mental health among individuals who are not experiencing a particular life stress.     

Many stimuli are frightening,but some are more frightening than others: The contributions of preparedness,dangerousness, and unpredictability to making a stimulus fearful

The nonrandom distribution of situational fears has been explained by evolutionary survival relevance of specific fears. Thirty-eight stimuli were taken from the literature on preparedness and were scored on fearfulness, objective dangerousness, and spatiotemporal unpredictability by three separate groups of students. The same items were scored on survival relevance by 15 biologists. Fearfulness of cues significantly correlated not only with survival relevance but also, and even more strongly, with dangerousness and unpredictability. While the fear/survival relevance association virtually disappeared when the unpredictability contribution was partialed out, the fear/unpredictability correlation was only marginally affected when controlling for survival relevance. This suggests that nonrandomness of feared stimuli may result from the spatiotemporal unpredictability that is attributed to these stimuli. The current practice of using snakes and spiders as phobia-relevant, and flowers and mushrooms as neutral, cues was not justified by the ratings of the 15 independent experts.This study was supported in part by a grant from the Dutch Organization for Fundamental Research (ZWO/Psychon, 560-268-001).     

Risk and behavior: The mediating role of risk appraisal

The main issue of this paper concerns the mediating role of risk appraisal in the relation between past and future behavior. We expected previous risky behavior to heighten risk appraisal, which, in turn, should stimulate preventive behavior. Results ofthree tests of this mediation hypothesis showed that past behavior was strongly related to future behavior; people who behaved hazardously in the past indicated that they tend to do so in the future. Generally, the expected relation between past behavior and risk appraisal was supported. More risky behavior in the past was associated with a heightened risk appraisal. Results also indicate a relation between risk appraisal and future behavior, but in the opposite direction as predicted. Heightened risk appraisal was related to increased levels of risk in future behavior. When predicting future behavior by both risk appraisal and past behavior the effect of risk appraisal on future behavior disappeared, while past behavior remained a strong predictor of future behavior. In a few cases risk appraisal still predicted future behavior when past behavior was controlled for. Unfortunately, these cases showed the opposite relation; i.e., heightened risk appraisal was related to more risky future behavior. Implications of these findings for research on the role of risk appraisal will be discussed.